In this photo provided by China's Xinhua News Agency, rescuers walk into the accident site to search for survivors in Jingtai County of Baiyin City, northwest China's Gansu Province, Sunday, May 23, 2021.

At least 21 ultramarathon athletes died after brutal weather swept across a mountainous area of northwest China during a race, state media reported Sunday.

Another 151 participants in the 100 kilometer race – 62 miles – in Baiyin City in Gansu Province were accounted for, and eight people were hospitalized in stable condition, local rescue headquarters reported.

The officials cited a sudden, dramatic change in the weather during Saturday’s race in the Yellow River Stone Forest. At about 1 p.m., hail  freezing rain and gales hit the area of the race’s high-altitude stage as runners were climbing 6,500 feet above sea level in shorts and T-shirts.

Some participants posted videos requesting help in a WeChat group chat. Some of the participants went missing and the race was halted. Local governments initiated an emergency response and organized over 1,200 rescuers to search for the missing athletes in amid mudslides and localized flooding.